PROJECT SUMMARY/ABSTRACT The Biospecimen Core will continue to provide high quality annotated specimens and expert pathology consultation to enhance the projects of Case GI SPORE investigators. This process will continue the longstanding, successful, collaborations between the members of the Core and the individual project investigators. During the course of these collaborations the Core has developed an extensive biospecimen archive derived from over 13,000 patients. Previously, the Core has supplied high quality annotated specimens leading to the discovery of 15-Prostaglandin Dehydrogenase as an important tumor suppressor gene in colon carcinogenesis ? the basis of Project 1; the African American colon cancer 15 gene-panel ? the basis of Project 2; methylated vimentin as a biomarker of Barrett's Esophagus ? the basis of Project 3; and the discovery of unique glutamine metabolism in PIK3CA mutated colon cancers ? the basis of Project 4. The Core also provided significant support to the SPORE's Career Enhancement and Pilot Projects Programs. The Core has an extensive archive of colon neoplasms from over 4,800 patients including 2,292 primary colon cancers of known pathologic stage and databased clinical follow-up as well as a substantial number of cancer metastases. Frozen material from 1053 of these cases is also banked with matched normal controls. The Core also has 350 esophageal cancers and Barrett's esophagus paraffin specimens as well as 134 frozen esophageal specimens. Many of these samples have undergone extensive molecular analysis ? enabling sophisticated translational studies. The Core works with the Case Comprehensive Cancer Center to make available to the SPORE a wide variety of techniques and technologies in a cost effective manner. The Core will organize all prospective GI biospecimen procurements and distribution to SPORE investigators as well as provide access to its existing tissue archive resource. The Core will support the projects of this application by identification of tissues of interest to investigators both from the Core archive and from prospective accrual. The Core will provide histopathological quality control for tissue sections, along with project specific morphology case reviews and will oversee and provide longitudinal follow-up of clinical outcomes linked to these tissues. The Core will also provide tissue microarray sections for tissue targets of interest, expertise in immunohistochemistry and in situ hybridization assessment and samples appropriate for specific studies. The primary objective is to provide a resource that contributes significantly to the translational goals and endpoints of the individual projects and to facilitate cooperation between other GI SPOREs.